Mobile communication terminal with improved isolation

Abstract

A terminal includes a main ground disposed on a substrate, a first antenna connected to the main ground, a second antenna spaced apart by a reference distance from the first antenna and connected to the main ground, and a dummy pattern disposed within a reference proximity to at least one of the first antenna and the second antenna

What is claimed is: 
     
         1 . A terminal, comprising:
 a main ground disposed on a substrate;   a first antenna connected to the main ground;   a second antenna spaced apart by a reference distance from the first antenna and connected to the main ground; and   a dummy pattern disposed within a reference proximity to at least one of the first antenna and the second antenna.   
     
     
         2 . The terminal of  claim 1 , wherein the dummy pattern is coupled with the at least one of the first antenna and the second antenna to provide a resonance. 
     
     
         3 . The terminal of  claim 1 , wherein the first antenna supports a first frequency range and the second antenna supports a second frequency range. 
     
     
         4 . The terminal of  claim 3 , wherein the first frequency range and the second frequency range are adjacent to one another. 
     
     
         5 . The terminal of  claim 1 , wherein the first antenna supports a Long Term Evolution (LTE) frequency band. 
     
     
         6 . The terminal of  claim 1 , wherein the second antenna supports a Global Positioning System (GPS) frequency band. 
     
     
         7 . The terminal of  claim 1 , wherein the dummy pattern provides a third resonance in a resonance frequency band of the second antenna. 
     
     
         8 . The terminal of  claim 1 , wherein the dummy pattern provides a third resonance based on an inductance and a capacitance of the dummy pattern, in which the inductance is based on a length of the dummy pattern. 
     
     
         9 . The terminal of  claim 8 , wherein the capacitance is based on a first distance between the dummy pattern and the main ground, and a second distance between the dummy pattern and the first antenna. 
     
     
         10 . The terminal of  claim 8 , wherein the capacitance is based on a first distance between the dummy pattern and the main ground, and a second distance between the dummy pattern and the second antenna. 
     
     
         11 . The terminal of  claim 1 , wherein a length of the dummy pattern overlapping an antenna coupled to the dummy pattern is directly related to a width of a resonance frequency band of the second antenna. 
     
     
         12 . The terminal of  claim 1 , wherein a distance between the dummy pattern and an antenna coupled with the dummy pattern is inversely related to a width of a resonance frequency band of the second antenna. 
     
     
         13 . The terminal of  claim 1 , wherein if the dummy pattern is coupled to the first antenna, at least one of a resonance provided by the first antenna, a resonance provided by the second antenna, and a third resonance provided by the dummy pattern reduces antenna radiation of the first antenna with respect to a resonance frequency of the second antenna. 
     
     
         14 . The terminal of  claim 1 , wherein if the dummy pattern is coupled to the second antenna, an increase in attenuation of a resonance of at least one of the first antenna and the second antenna improve isolation therebetween. 
     
     
         15 . The terminal of  claim 1 , wherein the dummy pattern is disposed in a direction in which the main ground extends. 
     
     
         16 . The terminal of  claim 1 , wherein the dummy pattern is disposed in a direction perpendicular in which the main ground extends. 
     
     
         17 . A terminal, comprising:
 a main ground disposed on a substrate;   a first antenna connected to the main ground;   a second antenna spaced apart by a reference distance from the first antenna and connected to the main ground;   a first dummy pattern disposed within a reference proximity to the first antenna;   a second dummy pattern disposed within a reference proximity to the second antenna; and   a switching device to turn on at least one of the first dummy pattern and the second dummy pattern.   
     
     
         18 . A method for improving isolation, comprising:
 determining whether a first antenna is to be used;   determining whether a second antenna is to be used;   determining whether the first antenna and the second antenna of a terminal uses adjacent frequency bands; and   connecting a dummy pattern corresponding to at least one of first antenna and the second antenna to a main ground,   wherein the dummy pattern is connected according to the determinations.   
     
     
         19 . The method of  claim 18 , wherein the dummy pattern is disposed in a direction perpendicular in which the main ground extends. 
     
     
         20 . The method of  claim 18 , wherein if only the second antenna is used among the first antenna and the second antenna, a dummy pattern corresponding to the first antenna is connected to the main ground. 
     
     
         21 . The method of  claim 18 , wherein if only the first antenna is used among the first antenna and the second antenna, the dummy pattern corresponding to the second antenna is connected to the main ground. 
     
     
         22 . The method of  claim 18 , wherein if a frequency band of the first antenna is closer to a frequency band of the second antenna, the switching device connects the dummy pattern corresponding to the second antenna to the main ground. 
     
     
         23 . The method of  claim 18 , wherein, if a frequency band is not in use or is outside of a reference range of a frequency band of the second antenna, the switching device connects the dummy pattern corresponding to the first antenna to the main ground.